Spring suspension for wheeled vehicles



Dec. vl', 1942. KjMlTCHELL 2,303,653

SPRING SUSPENSION FOR WHEELED VEHICLES Filed June 1'7, 1941` v 2 Sheets-Sheet ll Dec.'1, 1942. l.. K. MITCHELL SPRING SUSPENSION FOR WHEELED VEHICLES Filed June 17, 1941 2 sheets-sheet 2 57ml? l I l l l/ I, s||| l f y IIIII Patented Dec. `1, 1942 v` SPRING SUSPENSION FOR WHEELED l VEHICLES Louis K. Mitchell, Tampa, Fla.` I

Application June 17, 1941, Serial No.`398,458 claims.A (01.2674-1-11) This invention relates to spring suspensions by means of which wheeled vehicles maybeveectively cushioned against shocks ,ofthe= road and against side sway.

A primary object of the invention is to provide n a leverage by which the force ofthev shock on one end of an axle may be resisted simultaneously by springs at both sides of the vehicle.

AIurther object of Athe invention is to .utilize the inertia of a vehicle at the pivoted center of a lever which will convert an upward thrust at one endinto a downward thrust at-'the other,

In front of the axle and suspended betweenthe members 8, 8, ofthe chassis are brackets I2 and I3 forming supports for the pivot I4 of a lever I5. At each end, this leverv is bent upward to form whereby the upward force of a shock on one side is directed toward the roadbed on the other side and is resisted primarily by the tires and by the springs on both sides and only secondarily by the body through a smaller range of movement.

A still further object is vto provide resilient means for holding the body of the vehicle against i tilting or side sway, such means cooperating with the leverage to apply additional tension upon the body on the side receiving an upward thrust, thereby, in effect, increasing the inertia of the body as against side sway in proportion tothe shock. 1

An advantage of the central pivoting of the lever at the transverse center of either end of 'the body is that the inertia of half of the total mass is available to resist the thrust, and because of the resilient connection between each end" of the lever and the adjacent end of the axle, the axle is in effect pivoted to the body centrally upon yielding supports which permit many movements to neutralize each other.

In the drawings illustrating certain preferred forms of the invention, Figure 1 is a front eleva-'- tion of the forward endr of a vehicle, parts being shown in section and parts being broken away;

Fig. 2 is a vertical section on the line 2-2 of Fig. l; Fig. 3 is a fragmentary view on the line 3-3 of Fig. 1; Fig. 4 isa plan view of the structure of Fig. 1; Fig. 5 is a fragmentary elevation showing a modification of the structure of Fig. 3; Fig. 6 is a front elevation of a modication using-leaf Vsprings as the lever; and Fig. '7 is a fragmentary side elevation of thevstructure of Fig. 6.

The front axle of a vehicle is indicated at I and its supporting wheels at 2. A radius rod 3, securedat 4, 4, on the axle and having a ball joint 5 pivoted ina bearing 6 onV a transverse member I connecting the side members 8, 8, of the. chassis, serves to hold the axle'erect and Aagainst movement longitudinally of the chassis. 'I'he central portion of the rod 3is pivotally mounted in a sleeve 9 carried at the forward end of arms I0, I0, which are pivotally mounted at their rear ends horizontally upon the chassis to permit vertical movement of the yradius rod toward and from the body while preventing horizontal angular movement of the axle with respect 60 to the chassis.

an arm I6 having a portion II-extendng sidewise abovethe axle I. The portion I1 lies within a loop I8 on a cap I9 which rests upon the upper end of avcoiledspring 20,-'the lower end of which is held in'a cup v2| upon the axle, `A second coiled spring 22 isshown in Figs. 1 and4 within the spring 20, this second spring being Ashorter than the spring 20 to act onlyas ar reinforcingl spring for extra loads or excessive shocks.-

By this arrangement, the lever I5y bears downward at each'end upon a spring 20, and at its center pivot I4, the lever bears half of the weight of the chassis and of whatever load the chassis may carry. It will, of course be. Aunderstood that this arrangement may be repeated or duplicated at the other end of the chassis, land this-duplication has not been illustrated.

Near each end of the lever I5 is a pivot 23 from which a.' rod 24 extends upward and sidewise across the longitudinal center of the chassis to -a cylindrical casing 25 upon a chassis member 8. Within this vcasing is a spring 26 to resist outoiiset near their central portions at'28, to avoid interference with each other. y.

In Fig. 5, a modification is shown in which the lever l5 has a projecting stud 29 to which are pivoted shackles 30` which extend upward to a pivotal support 3| on the cap I9, these shackles, stud, andpivot replacing the arm I 6. and `its sidewise extension I'I of the previously described structure. p l

- Another modification of the invention is illustrated in Figs. 6 and 7, in which the radius rod 3 has its forward ends formed as perches 32 to carryshackles 33 upon which arepivotally supported the ends of a leaf-spring assembly 34 which has its center held within a clamp 35 piv-` struction upon the same pivots that support the l ends of the spring assembly upon the lower ends ofthe shackles. l

The operation of the devicemay perhaps best be understood by a ystudy of Fig. 1. It will be seen that if thewheel 2 on either side is thrust upward, the axle I will belifted carrying'the cup' 2| upward to compress the spring 20. The pressureof this spring on the cap I9 will cause the arm I6 to lift that end ofthe'lever I5 and since the inertia of the load will hold the pivot I4 momentarily stationary,v the lever will swing on its vas pivot, causing the other end'of the lever to compress the spring 20, this being resisted by the axle and the wheel and the tire at that end.

Thus both of the springs 20 act simultaneously to cushion any upward shock on either wheel.

Sidewise movement of the body causing the chassis to rock will be resisted by the springs 26,

the stabilizing rods 24, the centralizing lever I5,

l stabilizing rod 24 which will compress they` spring 26 on the sidevwhereA the axle is lifted. Since the tilting movement ofthe body with respect to the lever is resisted by the springs26, any in- -crease in the tension of these springs will cause greater resistance to a tilting movement of the body upon the lever or of the lever on the body.

If the body'bears a greater` load, thesprings 20 will evidently be more greatly compressed and this will also cause an increase in resistance to the pivotal movement of the lever. The eiect of the increase in the tension of the spring 26 is substantially the same as is produced by an increase in the load, and this increase in tension is proportional to the upward thrust on the wheel.

While roadbuilders endeavor to construct smooth pavements, there are always irregularities in road surfaces. As a vehicle travels along a roadway, each wheel, independently of the others, has three possible phases of movement: it may be going upward,V or going downward, or it may move neither up nor down.

When the two wheels at opposite ends of the same axle vin the present structure are both on a level surface there is no'vertical movementand hence no tilting of the lever. When one wheel `goes up and the other simultaneously goes down and both then return simultaneously to the level,

the reverse movement of the ends of the lever will evidently cause no vertical movement of the body and this will evidently be true no matter how often this tilting movement of the lever may be repeated or whether the tilting movement be fast or slow.

When one wheel remains level and the other goes up, the pivot of the lever will evidently lift only half as much as the end, and since the spring on the other end of the lever is compressed by the tilting of the lever, the upward thrust at the center is a small'fraction of that at the lifting end of the lever. When one wheel remains level and the other goes down, the pivot will fall only v half as much as the end of the lever, and with this release in pressure, the -spring at the other end of the lever will expand resistr the lowering of the pivot. 1

If V-both wheels lift simultaneously or drop simultaneously, there will evidently be no tilting movement of the lever, but even in these cases, the springs 20 will function to cushion the shocks well as in most ordinary suspensions.

The structures illustrated are to be considered merely as typical examples of possible embodiments ofvthis invention since many changes in details of construction will be necessary to adapt the device to different vehicles withoutudeparture from the essence of the invention as set forth in what is claimed.

I claim:

l. A vehicle suspension comprising an axle, a frame, having a transverse member, a lever pivoted upon the transverse memberof the frame adjacent to the axle and substantially parallel therewith, a spring carried by the axle near each end thereof, means upon the lever at each end thereof engaging the adjacent spring upon the axle, two tension rods, each rod being pivoted at its outer end near the end of the lever and secured at its inner end to the frame, and each rod having a spring connected therewith to restrain movement of the lever relative to the frame.

2. In combination, an axle, a spring carried by the axle on each sideof its longitudinalcenter, a' frame having a transverse member, a lever pivoted centrally of the transverse member and supported at its ends upon the springs carried by the axle, each end of the lever having a rod pivoted thereto and extending therefrom across the longitudinal center ofV the transverse frame member, a securing means `upon the frame'for the end of eachrod remote fromk the lever, a resilient element interposed between each rod and the securing member whereby the movement of each rod is `resisted by the resilient velement and whereby tilting movement of the frame upon the lever is restrained by the resilient elements. l

3. vA vehicle body support comprising an axle, a leverl pivoted centrally upon the body and supported at its ends by the axle, and tensionmeans extending from each sidevof the body downward across thecentral pivotal' axis of` the ylever and engaging an outer end of the lever onthe'opposite side of the axis for restraining tilting movement of the body on the lever, one of the supporting. 'means comprising a resilient element permitting vertical movement of the body-.upon the axle.

4. A vehicle suspension comprising an axle. a frame, a lever substantially parallel with the axle and pivoted centrally of its length atthe transl verse center of the frame, coil springs carried by posite sides of the frame at their rear ends, and

the rear end of the radius rod having a pivotal connection with the frame.

5. A vehicle body support comprising an axle, aspring carried by the axle near each end thereof the body having a transverse frame member, a lever pivoted centrally upon the transverse member adjacent to the axle-and having means at each end engaging the adjacent spring upon the axle to be supported thereby, and means for restraining tilting movement of the body comprising two tension members interposed between the body and the lever, each member being attached at one end to the lever near one outer end thereof and being attached at the other end to ia rportion of the body above and upon the opposite side of -the point at which the lever is pivoted` to the 

